Detection rules › Kusto Query Language

Potential re-named sdelete usage (ASIM Version)

Author
Microsoft Security Research
Source
upstream

'This detection looks for command line parameters associated with the use of Sysinternals sdelete (https://docs.microsoft.com/sysinternals/downloads/sdelete) to delete multiple files on a host's C drive. A threat actor may re-name the tool to avoid detection and then use it for destructive attacks on a host. This detection uses the ASIM imProcess parser, this will need to be deployed before use - https://docs.microsoft.com/azure/sentinel/normalization'

MITRE ATT&CK coverage

TacticTechniques
Defense EvasionT1036 Masquerading
ImpactT1485 Data Destruction

Event coverage

ProviderEvent IDTitle
Sysmon1Process creation
Sysmon5Process terminated
Security-Auditing4688A new process has been created.
Security-Auditing4689A process has exited.

Stages and Predicates

Stage 1: source

imProcess

Stage 2: where

CommandLine match ["accepteula", "-s", "-r", "-q"]

Stage 3: where

not
  Process ends_with "sdelete.exe"

Stage 4: where

not
  CommandLine match "sdelete"

Stage 5: extend

Exclusions

Top-level NOT(...) conjuncts — predicates this rule actively suppresses.

StageFieldKindExcluded values
1Processends_withsdelete.exe
1CommandLinematchsdelete

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
CommandLinematch
  • -q corpus 2 (sigma 2)
  • -r corpus 3 (sigma 3)
  • -s corpus 2 (sigma 2)
  • accepteula corpus 3 (sigma 3)